Accordingly, the present invention is directed to a trench capacitor that obviates one or more of the problems due to limitations and disadvantages of the related art. The present invention also provides a method for manufacturing a trench capacitor.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the trench capacitor and method for manufacturing the trench capacitor particularly pointed out in the written description and claims thereof, as well as the appended drawings.
The present invention provides a trench capacitor that includes an electrode, a storage node and a dielectric layer. The electrode includes a first conductive area formed in a trench provided in a substrate, and a second conductive area extending from a bottom of the trench. The second conductive area is electrically coupled to the first conductive area and spaced horizontally apart from the first conductive area. The storage node includes a first conductive extension extending into a first dielectric space provided between the first conductive area and the second conductive area of the electrode. The storage node also includes a second conductive extension extending into a second dielectric space provided within the second conductive area of the electrode. The dielectric layer electrically insulates the electrode from the storage node.
Also in accordance with the present invention, a trench capacitor is provided. The trench capacitor is formed in a trench within a semiconductor substrate and includes an electrode, a storage node, and a dielectric layer. The electrode has a double-crown structure that includes an outer conductive crown comprising a doped semiconductor substrate and an inner conductive crown spaced apart from the outer conductive crown. The inner conductive crown is electrically coupled to the outer conductive crown. The storage node extends into a first dielectric space formed between the outer conductive crown and the inner conductive crown, and also extends into a second dielectric space formed within the inner conductive crown. The dielectric layer electrically insulates the electrode from the storage node.
Still in accordance with the present invention, a trench capacitor is provided. The trench capacitor is formed in a trench within a semiconductor substrate and includes an electrode, a dielectric layer, and a storage node. The electrode has a plurality of electrode prongs. Each of the electrode prongs is electrically coupled to the other electrode prongs, and at least one electrode prong is comprised of a portion of a doped substrate. The storage node has a plurality of storage node prongs, with each of the storage node prongs being electrically coupled to the other storage node prongs. At least one of the storage node prongs extends into a dielectric space provided between two of the plurality of electrode prongs. The dielectric layer electrically insulates the electrode from the storage node.
The present invention also provides a method for manufacturing a trench capacitor. The method includes forming a trench within a substrate; doping the substrate to form a first conductive area; forming a first dielectric layer to electrically insulate the first conductive area; forming a second conductive layer contiguous with the first dielectric layer; forming a second dielectric layer contiguous with the second conductive layer; removing a bottom portion of the first dielectric layer, the second conductive layer, and the second dielectric layer; forming a third conductive layer in the trench to electrically couple to the first conductive area; electrically insulating the third conductive layer; removing an upper sidewall portion of the first dielectric layer, the second conductive layer, the second dielectric layer, and the third conductive layer; forming a fifth dielectric layer on an upper sidewall of the trench; forming a fourth conductive layer in a lower portion of the trench; and forming a fifth conductive layer on the fourth conductive layer in the trench to electrically couple the fourth conductive layer and the second conductive layer.
Still in accordance with the present invention, a method for manufacturing a trench capacitor is provided. The method includes providing a first conductive area of an electrode in a substrate surrounding a trench; providing a second conductive area of the electrode, the second conductive area comprising at least a vertical wall extending from a bottom of the trench, the second conductive area being electrically coupled to the first conductive area and spaced apart from the first conductive area; providing a first conductive extension of a storage node, the first conductive extension extending into a first dielectric space provided between the first conductive area and the second conductive area of the electrode; providing a second conductive extension of a storage node, the second conductive node extending into a second dielectric space provided within the second conductive area of the electrode; and providing a dielectric layer electrically insulating the electrode from the storage node.